Probably too late to help you now, but in case anyone else is reading this and equally 'impressed' with Wordpowers website, a quick heads up about it:
I won't go into the gory details over fear of being sued, but our esteemed Dave himself stopped allowing Wordpower to advertise on his website for teachers due to the sheer volume of complaints this company generated over the way it dealt with it's employees. There was an entire page dedicated to ex-employee experiences until the manager/owner of Wordpower had his lawyer threaten to sue Dave and, bizarrely, threaten to report Dave to the FBI and CIA (!)

I could tell you my horror story with this lot, but as you see Wordpower is very keen to suppress, bully and threaten anyone and everyone.

I'll leave it to your imaginations as to just what sort of practises a company would do for Dave to refuse money from them to advertise for staff. How bad must it be if he'd rather be a little poorer than accept their money?!